Conventional electronic thermometer systems use a sensing element, e.g., thermocouple, thermistor, diode whose impedance changes, or voltage or current output varies as a function of the temperature to which it is exposed. The signal is submitted to an analog measuring or indicating device such as a galvanic meter which displays the temperature. Such systems are satisfactory in sophisticated technical and scientific environments where personnel are accustomed to such equipment. However, recently, electronic thermometers have become increasingly more widely used in less technically sophisticated areas such as patient care by medical personnel. Electronic thermometers quickly rivaled mercury thermometers in the area of cost and speed. The cost of using an electronic thermometer with disposable probe covers is compatible with the cost of purchase of, plus routine sterilization of mercury thermometers, and electronic thermometers can measure temperatures much more quickly conserving expensive and scarce personnel time. This area of application demands a more easily readable as well as smaller, lighter, more compact and less expensive electronic thermometer. In view of present electronic technology these aims are best served by making maximum use of digital as opposed to analog implementation. One attempt to create an electronic thermometer using at least some digital circuitry resulted in a system in which the temperature sensing probe provides a signal to a bridge circuit. When the temperature sensed exceeds some predetermined reference, the bridge imbalance causes a signal to step a counter and charge a capacitor. The counter causes a resistor to be inserted in the bridge to balance it. Further increase in temperature causes the cycle to be repeated until, the capacitor has been charged sufficiently to trigger a switch to display the temperature: when the changes in temperature are occurring at a slow enough rate relative to the thermal time constant of the thermometer it is assumed that the temperature sensed is at its final temperature within the desired accuracy. While such a system does operate in a digital fashion it requires many switches, extra resistors and circuitry in a large, heavy and expensive system. Increased accuracy to such a system is acquired at the cost of increased numbers of resistors and switches.